We are continuing in our studies on tumor immunity in animals and man. New serological assays have been developed for measuring antibody binding to surface localized tumor antigens (Brown et al., J. Immunol. Methods, in press, Hellstrom et al., J. Immunol. Methods in press), and these assays are being used to characterize surface antigens in chemically induced mouse sarcomas. The animal work will then be used as a model for a similar approach to human tumor serology, studying melanomas in particular. Another part of our studies concerns an analysis of the cell-mediated immune response of patients with tumor, mostly melanoma, to tumor associated antigens present on authochthonous and allogeneic cells from the respective tumor types.